Before the introduction of junction box technology, wire harnesses for each automobile had to be individually tailored for particular vehicle options. Wire harnesses were overly complex, required unreliable and costly splicing, and necessitated high labor costs. Achieving standardization of vehicle wiring and the concomitant savings associated therewith, such as high reliability and low labor and supply costs, was impossible.
With the introduction of printed circuit junction boxes, wire harness complexity and cost were reduced since the junction boxes provided a plurality of previously individually wired pathways for the centralized distribution of electrical signals. Wire harness standardization was possible to a limited extent, yet individual wire harnessing was still reguired for various vehicle options, particularly those requiring additional e1ectrical components for proper operation. The electrical components (such as a diode) were generally hard wired into an appropriate harness causing the harnesses to be bulky, difficult to service and install, and of little use for other vehicle options. Because of the individual wiring reguired, complete standardization of automobile wiring has not been achieved; various wire harnesses are required, and junction boxes require differing internal circuitry or complicated external connections to accommodate each vehicle option.
The prior art addresses the problem of standardization by attempting to make junction boxes more flexible to accommodate standardized harnesses and available options. U.S. Pat. No. 4,208,080 to Teagno dislcoses a junction box housing printed circuit boards connected by a plurality of individual stakes that are used to accommodate different vehicle functions by connecting the appropriate circuit paths imprinted in the circuit boards. The box is complicated, has a high margin for error (particularly relating to misinsertion of the stakes), and insertion of the stakes requires a great deal of labor. U.S. Pat. No. 4,552,423 to Swengel, Jr., discloses a single programmable shunt (11) having prongs (13) to provide multiple connections between a socket (25) and selected terminals to connect a selected circuit. However, the shunt is made of a conducting material which limits its ability to connect more than one discrete circuit. Similarly, U.S. Pat. No. 4,464,003 to Goodman et al., discloses a programmable bus bar (20) made of a conductive material to interconnect selected of conductors (18). The bus bar can only interconnect one discrete circuit. U.S. Pat. No. 4,487,464 to Kirschenbaum discloses a plurality of different bus bars (23, 30, 33, 40, 43) making the required electrical connections for a plurality of discrete circuits. A different bus is required to connect each discrete circuit, engendering high labor costs and high probability for error particulary relating to the insertion (or misinsertion) of each bus.